A system for applying radiation to a target region within a subject is, for instance, a high dose rate (HDR) brachytherapy system. An HDR brachytherapy system comprises a brachytherapy catheter which is introduced into the target region, wherein within the brachytherapy catheter a radioactive radiation source is moved to different dwell positions at which the radioactive radiation source is located for respective dwell times. The target region is treated by radioactive radiation emitted by the radioactive radiation source at the different dwell positions for the respective dwell times.
The radiation emitted by the radiation source destroys, for instance, cancerous tissue primarily through the generation of oxygen radicals that attack the tumor DNA Cells to be destroyed may only contain a relatively low amount of oxygen, which may lead to a reduced effectiveness of the application of the radiation.